A headlight equipped with an optical deflector manufactured by using MEMS (Micro Electro Mechanical Systems) technology is known (e.g.: Patent Literature 1).
The optical deflector equipped in the headlight in Patent Literature 1 has a reflection unit for reflecting light and an actuator driven by a driving voltage and reciprocating and rotationally moving the reflection unit around two rotation axes orthogonal to each other. According to this optical deflector, the light incident to the reflection unit from a laser light source or the like is reflected by the reflection unit reciprocated and rotationally moved around the two rotation axes and is emitted toward an irradiation region in front. By means of this light, the irradiation region in front is scanned in a horizontal direction and a vertical direction.
In order to reciprocating and rotationally moving the reflection unit at a predetermined frequency (the frequency of the reciprocating and rotational movement of the reflection unit is equal to a scan frequency of scan light), the actuator is driven by a voltage with a waveform expressed by a sinusoidal wave or sawtooth wave in general.